1. Field of the Invention
The present invention relates to commercial irrigation systems and more particularly to improvements in circular irrigators adapted for commercial use.
2. Description of the Prior Art
In commercial applications such as agricultural production controlled irrigation is of paramount importance. Typically, in order to conserve the cost of pipe and other equipment circular or center pivot irrigation systems have been utilized. In such center pivot systems, the water is applied to a tubular spray head assembly at the pivoted end and the other end is advanced in a circle on a wheeled undercarriage. By this arrangement, large agricultural plots can be sprayed with minimal investment in hardware.
Devices of this kind are typically limited to a circular pattern of a radius determined by the shortest dimension of the plot to be irrigated. Thus, for example, in a rectangular plot the center of the plot determines the pivot position and the shortest dimension determines the radius of the irrigation pipe. As result of such limitations, the corners of the plot are normally not irrigated.
When applied to a typical 160 acre plot, at least 30 acres distributed through the corners do not receive adequate irrigation. To at least partly solve this problem, techniques have been developed in which the irrigation pipe is provided with a manually operated end gun opened during the sections of arc when corner irrigation is desired. The use of an end gun, however, still entails only a limited increase in an area covered since both the pressure required is high and the proper timing of the on and off cycle requires constant monitoring.